Multiple mirror concentrating solar collector assemblies are known for directing the rays from the sun to a common point by means of an array of mirrors. Typically, a large number of mirrors is used; and these mirrors are individually focused from a tracking apparatus onto a common point for utilization of the solar energy reflected by the mirrors onto that point. Large scale collector assemblies use the focused heat for a variety of purposes. Some operate a boiler for generating electricity. Other such assemblies are used in a hot water system for producing a source of hot water. The apparatus on which the mirrors are mounted operates to track the relative movement of the sun and the earth on a daily an annual cycle from east to west, and from north to south. Sophisticated equipment has been developed for performing this function to maximize the effectiveness of the collection of solar energy by the multiple mirror arrays. A typical solar collector of this type is disclosed in the U.S. Pat. No. 4,056,313 to Arbogast.
From time to time, it becomes necessary to refurbish or replace different ones of the individual mirrors of a concentrating solar collector. This usually is a relatively labor intensive, time consuming operation, because the mirrors are permanently attached to individual mounting points on the underlying apparatus. In some locations, it is desirable to remove the mirrors and store them for protection during extreme weather conditions, such as snow, hail, high winds and the like. The standard mountings for such mirrors often preclude ready removal and storage when such adverse weather conditions threaten, again, because of the large amount of time and labor required to effect the removal and replacement of the mirrors. As a consequence, particularly in situations where hail or heavy snow conditions exist, damage to the mirrors can occur, because of an inability to remove the mirrors in sufficient time to prevent such damage.
Instead of using glass mirrors, inexpensive mirrors comprised of a foam backing, such as styrofoam or the like coated with a reflective thin film surface made of Mylar or other suitable materials, have been developed. The lightweight mirrors permit less rugged support structures to be used, in contrast to the rugged support structures which must be employed with heavy glass mirrors. In addition, when such inexpensive mirrors are damaged, they can be recycled or discarded at relatively low cost. The attachment of such inexpensive, lightweight mirrors, however, to the individual mounting positions on the solar collector apparatus has been subject to the same disadvantages which occur with respect to glass mirrors, namely the attachments are time consuming to make; so that initial installation and any subsequent replacement of the mirrors is a labor intensive operation.
It is desirable to provide a heliostat mirror assembly which facilitates the removal and replacement of mirrors on the solar collector, and which is efficient in operation and easy to use.